Raw files are text files found in the \raw\objects subfolder of Dwarf Fortress (used for world generation) and in \data\save\<region-name>\raw\objects (for already generated worlds). These files can be looked through to discover various specifics of game items, materials, and creatures, and can be changed to alter how the game behaves. They are sometimes referred to by players as just "the raws".

The \raw\graphics subfolder of Dwarf Fortress is used to store user-customizable graphics sets.

Dwarf Fortress is not an open source program, so most modding of the game is limited to altering the raws or doing memory hacking.

Duplicating the raw files can cause several bugs, and even crashes. The game gets very messy and buggy when you do it.

BODY_DETAIL_PLAN - similar to CREATURE_VARIATION, but used for defining tokens related to body parts (specifically materials, tissues, the assignment thereof, and body part positions, relative sizes, etc.)

BUILDING - custom workshops

CREATURE - creatures

CREATURE_VARIATION - variations that can be applied to creatures (eg, making them giants, or anthropomorphic). Technically a series of tokens that are added to or removed from the creature (essentially a set of templated changes)

DESCRIPTOR_COLOR - named colours for use with DESCRIPTOR_PATTERN objects (other purposes unknown)

DESCRIPTOR_PATTERN - patterns with colour combinations for use with creatures (other purposes unknown)

DESCRIPTOR_SHAPE - shapes with descriptions and variations. Previous versions used this for engravings, but their use in the current version is unverified as of yet.

TISSUE_TEMPLATE - defines templated tissues for use with BODY_DETAIL_PLAN objects or in creatures

Usually empty strings are used to divide different types of structures like the fine name and [OBJECT:] or different entries, however everything which is not a token besides the 1st string (which is the filename) is understood as comments and is not considered.

The tokens are enclosed in square brackets ([TOKEN:VALUES]).

When a world is generated, the raw files are copied from <game folder>/raw/ to <game folder>/data/save/REGION/raw/. It is currently unknown how much these can then be changed without breaking the save.